Add a helper function for checking whether a bit is set in the guest
features for a vdev as well as one that works on a feature bit set.

Convert code that open-coded this: It cleans up the code and makes it
easier to extend the guest feature bits.
Signed-off-by: NCornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>

Add virtio_{add,clear}_feature helper functions for manipulating a
feature bits variable. This has some benefits over open coding:
- add check that the bit is in a sane range
- make it obvious at a glance what is going on
- have a central point to change when we want to extend feature bits

Convert existing code manipulating features to use the new helpers.
Signed-off-by: NCornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>

Drop a bunch of code duplicated from virtio_config.h and virtio_ring.h.
This makes us rename event index accessors which conflict,
as reusing the ones from virtio_ring.h isn't trivial.
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
Reviewed-by: NThomas Huth <thuth@linux.vnet.ibm.com>

commit 1773d9ee (virtio-net: cleanup: init and exit function)
removed the definition of virtio_net_init(), but didn't remove its
declaration in the header.  Clean that up.

Cc: Markus Armbruster <armbru@redhat.com>
Signed-off-by: NGonglei <arei.gonglei@huawei.com>
Reviewed-by: NMarkus Armbruster <armbru@redhat.com>
Signed-off-by: NMichael Tokarev <mjt@tls.msk.ru>

For better code sharing, add a helper function that handles
reference counting of the virtio backend for virtio proxy devices.

Cc: Cornelia Huck <cornelia.huck@de.ibm.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: NGonglei <arei.gonglei@huawei.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Some CPU families can dynamically change their endianness. This means we
can have little endian ppc or big endian arm guests for example. This has
an impact on legacy virtio data structures since they are target endian.
We hence introduce a new property to track the endianness of each virtio
device. It is reasonnably assumed that endianness won't change while the
device is in use : we hence capture the device endianness when it gets
reset.

We migrate this property in a subsection, after the device descriptor. This
means the load code must not rely on it until it is restored. As a consequence,
the vring sanity checks had to be moved after the call to vmstate_load_state().
We enforce paranoia by poisoning the property at the begining of virtio_load().
Signed-off-by: NGreg Kurz <gkurz@linux.vnet.ibm.com>
Reviewed-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>

We currently have a virtio_is_big_endian() helper that provides the target
endianness to the virtio code. As of today, the helper returns a fixed
compile-time value. Of course, this will have to change if we want to
support target endianness changes at run-time.

Let's move the TARGET_WORDS_BIGENDIAN bits out to a new helper and have
virtio_is_big_endian() implemented on top of it.

This patch doesn't change any functionality.
Signed-off-by: NGreg Kurz <gkurz@linux.vnet.ibm.com>
Reviewed-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>

In order to migrate virtio subsections, they should be streamed after
the device itself. We need the device specific code to be called from
the common migration code to achieve this. This patch introduces load
and save methods for this purpose.
Suggested-by: NAndreas Färber <afaerber@suse.de>
Signed-off-by: NGreg Kurz <gkurz@linux.vnet.ibm.com>
Reviewed-by: NAlexander Graf <agraf@suse.de>
Reviewed-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>

Signed-off-by: NAndreas Färber <afaerber@suse.de>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Drop VirtioDeviceClass::init.
Signed-off-by: NAndreas Färber <afaerber@suse.de>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Temporarily allow either VirtioDeviceClass::init or
VirtioDeviceClass::realize.

Introduce VirtioDeviceClass::unrealize for symmetry.
Signed-off-by: NAndreas Färber <afaerber@suse.de>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Right now we have these pairs:

- virtio_bus_plug_device/virtio_bus_destroy_device.  The first
  takes a VirtIODevice, the second takes a VirtioBusState

- device_plugged/device_unplug callbacks in the VirtioBusClass
  (here it's just the naming that is inconsistent)

- virtio_bus_destroy_device is not called by anyone (and since
  it calls qdev_free, it would be called by the proxies---but
  then the callback is useless since the proxies can do whatever
  they want before calling virtio_bus_destroy_device)

And there is a k->init but no k->exit, hence virtio_device_exit is
overwritten by subclasses (except virtio-9p).  This cleans it up by:

- renaming the device_unplug callback to device_unplugged

- renaming virtio_bus_plug_device to virtio_bus_device_plugged,
  matching the callback name

- renaming virtio_bus_destroy_device to virtio_bus_device_unplugged,
  removing the qdev_free, making it take a VirtIODevice and calling it
  from virtio_device_exit

- adding a k->exit callback

virtio_device_exit is still overwritten, the next patches will fix that.

Cc: qemu-stable@nongnu.org
Acked-by: NAndreas Faerber <afaerber@suse.de>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

When the dataplane thread stops, its vring.c implementation synchronizes
vring state back to virtio.c so we can continue emulating the virtio
device.

This patch ensures that virtio.c's signalled_used_valid flag is reset so
that we do not suppress guest notifications due to stale signalled_used
values.
Suggested-by: NKevin Wolf <kwolf@redhat.com>
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>

Support virtio transports which can specify the vring alignment
(ie where the guest communicates this to the host) by providing
a new virtio_queue_set_align() function. (The default alignment
remains as before.)

Transports which wish to make use of this must set the
has_variable_vring_alignment field in their VirtioBusClass
struct to true; they can then change the alignment via
virtio_queue_set_align().
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Message-id: 1373977512-28932-5-git-send-email-peter.maydell@linaro.org

The MMIO virtio transport spec allows the guest to tell the host how
large the queue size is. Add virtio_queue_set_num() function which
implements this in the QEMU common virtio support code.
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Message-id: 1373977512-28932-4-git-send-email-peter.maydell@linaro.org

Old qemu versions required that 1st s/g entry is the header.

Since QEMU 1.5, patchset titled "virtio-net: iovec handling cleanup"
removed this limitation but a feature bit is needed so guests know it's
safe to lay out header differently.

This patch applies on top and adds such a feature bit to QEMU.
It is set by default for virtio-net.
virtio net header inline with the data is beneficial
for latency and small packet bandwidth - guest driver
code utilizing this feature has been acked but missed 3.11
by a narrow margin, it's pending for 3.12.

This feature bit is cleared by default when compatibility with old
machine types is requested.

Other performance-sensitive devices (blk and scsi)
don't yet support arbitrary s/g layouts, so
we only set this bit for virtio-net for now.
There are plans to allow arbitrary layouts there, but
no code has been posted yet.

Cc: Rusty Russell <rusty@rustcorp.com.au>
Reviewed-by: NLaszlo Ersek <lersek@redhat.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>

Add virtio_device_set_child_bus_name function.

It will be used with virtio-serial-x and virtio-scsi-x to set the
child bus name before calling virtio-x-device's init.
Signed-off-by: NKONRAD Frederic <fred.konrad@greensocs.com>
Tested-by: NCornelia Huck <cornelia.huck@de.ibm.com>
Message-id: 1367330931-12994-3-git-send-email-fred.konrad@greensocs.com
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

This removes the unused prototypes in virtio.h.
Signed-off-by: NKONRAD Frederic <fred.konrad@greensocs.com>
Message-id: 1366791683-5350-8-git-send-email-fred.konrad@greensocs.com
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

This clean the init and the exit functions and rename virtio_common_cleanup
to virtio_cleanup.
Signed-off-by: NKONRAD Frederic <fred.konrad@greensocs.com>
Message-id: 1366791683-5350-7-git-send-email-fred.konrad@greensocs.com
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

This remove virtio-bindings, and use class instead.
Signed-off-by: NKONRAD Frederic <fred.konrad@greensocs.com>
Message-id: 1366791683-5350-6-git-send-email-fred.konrad@greensocs.com
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

This remove the function pointer in VirtIODevice, and use only
VirtioDeviceClass function pointer.
Signed-off-by: NKONRAD Frederic <fred.konrad@greensocs.com>
Message-id: 1366791683-5350-5-git-send-email-fred.konrad@greensocs.com
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

This remove old init and exit function as they are no longer needed.
Signed-off-by: NKONRAD Frederic <fred.konrad@greensocs.com>
Tested-by: NCornelia Huck <cornelia.huck@de.ibm.com>
Acked-by: NAmit Shah <amit.shah@redhat.com>
Message-id: 1366790881-3026-7-git-send-email-fred.konrad@greensocs.com
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

They are unused since commit 5c7d0962.
Signed-off-by: NLuiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>

Recent changes need two functions to VirtioDevice. This just add them
into VirtioDeviceClass.
Signed-off-by: NKONRAD Frederic <fred.konrad@greensocs.com>
Tested-by: NCornelia Huck <cornelia.huck@de.ibm.com>
Message-id: 1365690602-22729-2-git-send-email-fred.konrad@greensocs.com
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

Many of these should be cleaned up with proper qdev-/QOM-ification.
Right now there are many catch-all headers in include/hw/ARCH depending
on cpu.h, and this makes it necessary to compile these files per-target.
However, fixing this does not belong in these patches.
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

As all virtio-blk-* are switched to the new API, we can remove the separate
init/exit for the old API.
Signed-off-by: NKONRAD Frederic <fred.konrad@greensocs.com>
Reviewed-by: NPeter Maydell <peter.maydell@linaro.org>
Message-id: 1363624648-16906-10-git-send-email-fred.konrad@greensocs.com
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

Done with this script:

cd hw
for i in `find . -name '*.h' | sed 's/^..//'`; do
  echo '\,^#.*include.*["<]'$i'[">], s,'$i',hw/&,'
done | sed -i -f - `find . -type f`

This is so that paths remain valid as files are moved.

Instead, files in hw/dataplane are referenced with the relative path.
We know they are not going to move to include/, and they are the only
include files that are in subdirectories _and_ move.
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Also move the 9p.h file to 9pfs/virtio-9p-device.h, for consistency
with the corresponding .c file.
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

Add a queue_index to VirtQueue and a helper to fetch it, this could be used by
multiqueue supported device.
Signed-off-by: NJason Wang <jasowang@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

Some device (such as virtio-net) needs the ability to destroy or re-order the
virtqueues, this patch adds a helper to do this.

Signed-off-by: Jason Wang <jasowang>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

Create the virtio-device which is abstract. All the virtio-device can extend
this class. It also add some functions to virtio-bus.
Signed-off-by: NKONRAD Frederic <fred.konrad@greensocs.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

some backends (notably vhost) can mask events
at their source in a way that is more efficient
than masking through kvm.
Specifically
- masking in kvm uses rcu write side so it has high latency
- in kvm on unmask we always send an interrupt
masking at source does not have these issues.

Add such support in virtio.h and use in virtio-pci.
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>

Pass nvqs to set_guest_notifiers. This makes it possible to
save on irqfds by not allocating one for the control vq
for virtio-net.
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>

Move bindings from opaque to DeviceState.
This gives us better type safety with no performance cost.
Add macros to make future QOM work easier.
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>

Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Move public headers to include/net, and leave private headers in net/.
Put the virtio headers in include/net/tap.h, removing the multiple copies
that existed.  Leave include/net/tap.h as the interface for NICs, and
net/tap_int.h as the interface for OS-specific parts of the tap backend.
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Commit 0d8d7690 introduced
a regression in virtio-net performance because it looks
into the ring aggressively while we really only care
about a single packet worth of buffers.
Reported as bugzilla 1066055 in launchpad.

To fix, add parameters limiting lookahead, and
use in virtqueue_avail_bytes.
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
Reported-by: NEdivaldo de Araujo Pereira <edivaldoapereira@yahoo.com.br>
Tested-by: NEdivaldo de Araujo Pereira <edivaldoapereira@yahoo.com.br>
Reviewed-by: NStefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>